Oral Compositions and Methods of Use

ABSTRACT

Described herein are oral care compositions comprising an amino acid; a combination of zinc ion sources; and a thickening system comprising a nonionic cellulose ether having a molecular weight of from about 300,000 to about 350,000; and a polysaccharide gum; along with methods of making and using same.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of priority from PCT/CN2016/086994,filed Jun. 24, 2016, the contents of which are hereby incorporated byreference in their entirety.

BACKGROUND

Arginine-based oral care compositions generally include some combinationof polymers, abrasive(s); and in some instances, additional activeingredients. In those instances where additional active ingredients areincluded and comprise cationic metal ions, e.g. zinc, maintaining thephysical stability of the composition is a challenge because of theinteraction between these cationic metal ions and certain polymericcomponents and abrasive systems.

The use of certain abrasives or specific concentrations of particularpolymers are two ways in which the stability issues have been addressed.However, these methods have generally been individually focused onstand-up (i.e., appearance on the brush) and squeezability frompackaging (toothpaste tubes). As such, there remains a need to reconcilethese physical stability concerns and processability. Certainembodiments of the present invention are designed to address this need.

BRIEF SUMMARY

Some embodiments of the present invention provide oral care compositionscomprising a basic amino acid in free or salt wherein the amino acid isselected from arginine, lysine, and a combination thereof; a combinationof zinc ion sources; and a thickening system comprising from about 0.5wt. % to about 2 wt. % of a nonionic cellulose ether; and from about 0.1wt. % to about 1 wt. % of a polysaccharide gum. In some embodiments, thenonionic cellulose ether is hydroxyethylcellulose and the polysaccharidegum is xanthan gum.

Other embodiments provide compositions further comprising a silicaabrasive which exhibits an approximately neutral pH when measured in anaqueous medium. Still further embodiments provide oral care compositionscomprising a basic amino acid in free or salt wherein the amino acid isselected from arginine, lysine, and a combination thereof; a combinationof zinc ion sources; a thickening system comprising from about 0.5 wt. %to about 2 wt. % of a nonionic cellulose ether; and from about 0.1 wt. %to about 1 wt. % of a polysaccharide gum; and a silica abrasive whichexhibits an approximately neutral pH when measured in an aqueous medium.

In some embodiments, the oral care compositions of the present inventiondemonstrate the ability to avoid viscosity loss and maintain staticyield stress over an extended period of time, e.g. after one year.

In one aspect the invention is an oral care composition (Composition1.0) comprising:

-   -   a. A basic amino acid in free or salt from, wherein the amino        acid is selected from arginine, lysine, and combinations        thereof; (e.g., free form arginine);    -   b. zinc oxide and zinc citrate;    -   c. a fluoride source (e.g., sodium fluoride); and    -   d. a silica abrasive which exhibits an acid pH when measured as        an aqueous slurry (e.g., prophy silica).

For example, the invention contemplates any of the followingcompositions (unless otherwise indicated, values are given as percentageof the overall weight of the composition):

-   1.01 Composition 1.0 wherein the silica abrasive which exhibits an    acid pH when measured as an aqueous slurry is prophy silica.-   1.02 Any of the preceding compositions wherein the silica abrasive    which exhibits an acid pH when measured as an aqueous slurry is    Sylodent 783.-   1.03 Any of the preceding compositions wherein the silica abrasive    exhibits a pH of 3.5-4.5 in an aqueous slurry of the abrasive.-   1.04 Any of the preceding compositions wherein the silica abrasive    which exhibits an acid pH when measured as an aqueous slurry is    present in an amount from 2 to 35 weight percent.-   1.05 Any of the preceding compositions wherein the silica abrasive    which exhibits an acid pH when measured as an aqueous slurry is    present in an amount from 3 to 15 weight percent.-   1.06 Any of the preceding compositions wherein the silica abrasive    which exhibits an acid pH when measured as an aqueous slurry is    present in an amount selected from 2 wt. %, 3 wt. %, 4% wt. %, 5 wt.    %, 6 wt. %, 7 wt. %, 8 wt. %, 9 wt. %, 10 wt. %, 11 wt. %, 12 wt. %,    13 wt. %, 14 wt. %, 15 wt. %, 16 wt. %, 17 wt. %, 18 wt. %, 19 wt.    %, 20 wt. %.-   1.07 Any of the preceding compositions wherein the basic amino acid    has the L-configuration (e.g., L-arginine).-   1.08 Any of the preceding compositions wherein the basic amino acid    is arginine or lysine is in free form.-   1.09 Any of the preceding compositions wherein the basic amino acid    is provided in the form of a di- or tri-peptide comprising arginine    or lysine, or salts thereof.-   1.10 Any of the preceding compositions wherein the basic amino acid    is arginine or lysine, and wherein the arginine or lysine is present    in an amount corresponding to 1% to 15%, e.g., 3 wt. % to 10 wt. %    of the total composition weight, about e.g., 1.5%, 4%, 50%, or 8%,    wherein the weight of the basic amino acid is calculated as free    form.-   1.11 Any of the preceding compositions wherein the amino acid is    arginine from 0.1 wt. %-6.0 wt. %. (e.g., about 1.5 wt. %).-   1.12 Any of the preceding compositions wherein the amino acid is    arginine from about 1.5 wt. %.-   1.13 Any of the preceding compositions wherein the amino acid is    arginine from 4.5 wt. %-8.5 wt. % (e.g., 5.0 wt. %).-   1.14 Any of the preceding compositions wherein the amino acid is    arginine from about 5.0 wt. %.-   1.15 Any of the preceding compositions wherein the amino acid is    arginine from 3.5 wt. %-9 wt. %.-   1.16 Any of the preceding compositions wherein the amino acid is    arginine from about 8.0 wt. %.-   1.17 Any of the preceding compositions wherein the amino acid is    L-arginine.-   1.18 Any of the preceding compositions wherein the amino acid is a    free form arginine.-   1.19 Any of the preceding compositions wherein the basic amino acid    is lysine (e.g., 2 wt. %, 3 wt. %, 4 wt. %, 5 wt. %, 6 wt. %),    (e.g., 4 wt. %).-   1.20 Any of the preceding compositions wherein the amino acid is    lysine from 1.0 wt. %-6.0 wt. %.-   1.21 Any of the preceding compositions wherein the amino acid is    lysine from about 1.5 wt. %.-   1.22 Any of the preceding compositions wherein the amino acid is    lysine from about 4.0 wt. %.-   1.23 Any of the preceding compositions wherein the amino acid is    L-lysine.-   1.24 Any of the preceding compositions wherein the amino acid is    free form lysine.-   1.25 Any of the preceding compositions wherein the amino acid is    arginine or lysine in partially or wholly in salt form.-   1.26 Composition 1.25 wherein the amino acid is arginine phosphate.-   1.27 Composition 1.25 wherein the amino acid is arginine    hydrochloride.-   1.28 Composition 1.25 wherein the amino acid is arginine    bicarbonate.-   1.29 Composition 1.25 wherein the amino acid is lysine phosphate.-   1.30 Composition 1.25 wherein the amino acid is lysine    hydrochloride.-   1.31 Composition 1.25 wherein the amino acid is lysine bicarbonate.-   1.32 Any of the preceding compositions wherein the amino acid is    arginine or lysine ionized by neutralization with an acid or a salt    of an acid.-   1.33 Any of preceding compositions wherein the composition is    ethanol-free.-   1.34 Any of the preceding compositions further comprising a fluoride    source selected from: stannous fluoride, sodium fluoride, potassium    fluoride, sodium monofluorophosphate, sodium fluorosilicate,    ammonium fluorosilicate, amine fluoride (e.g.,    N′-octadecyltrimethylendiamine-N,N,N′-tris(2-ethanol)-dihydrofluoride),    ammonium fluoride, titanium fluoride, hexafluorosulfate, and    combinations thereof.-   1.35 The composition of 1.34, wherein the fluoride source is    stannous fluoride.-   1.36 Any of the preceding compositions wherein the fluoride source    is a fluorophosphate.-   1.37 Any of the preceding compositions wherein the fluoride source    is sodium monofluorophosphate.-   1.38 The composition of 1.34, wherein the fluoride source is sodium    fluoride.-   1.39 Any of the preceding compositions wherein the fluoride source    is a fluoride salt present in an amount of 0.1 wt. % to 2 wt. % (0.1    wt %-0.6 wt. %) of the total composition weight (e.g., sodium    fluoride (e.g., about 0.32 wt. %) or sodium monofluorophosphate).-   1.40 Any of the preceding compositions wherein the fluoride source    is sodium fluoride in an amount about 0.32 wt. % based on the weight    of the composition.-   1.41 Any of the preceding compositions wherein the fluoride source    is a soluble fluoride salt which provides fluoride ion in an amount    of from 50 to 25,000 ppm (e.g., 750-2000 ppm, e.g., 1000-1500 ppm,    e.g., about 1000 ppm, e.g., about 1450 ppm)-   1.42 Any of the preceding compositions wherein the fluoride source    is sodium fluoride which provides fluoride in an amount from    750-2000 ppm (e.g., about 1450 ppm).-   1.43 Any of the preceding compositions wherein the fluoride source    is selected from sodium fluoride and sodium monofluorophosphate and    which provides fluoride in an amount from 1000 ppm-1500 ppm.-   1.44 Any of the preceding compositions wherein the fluoride source    is sodium fluoride or sodium monofluorophosphate and which provides    fluoride in an amount of about 1450 ppm.-   1.45 Any of the preceding compositions wherein the pH is between 6.0    and 10.5, e.g., 7.0 to 9.0, e.g., about 8.0.-   1.46 Any of the preceding compositions further comprising calcium    carbonate.-   1.47 The composition of 1.46, wherein the calcium carbonate is a    precipitated calcium carbonate high absorption (e.g., 200/% to 300/%    by weight of the composition) (e.g., 25% precipitated calcium    carbonate high absorption).-   1.48 The composition of 1.47, further comprising a precipitated    calcium carbonate—light (e.g., about 10% precipitated calcium    carbonate—light) (e.g., about 10% natural calcium carbonate).-   1.49 Any of the preceding compositions further comprising an    effective amount of one or more alkali phosphate salts, e.g.,    sodium, potassium or calcium salts, e.g., selected from alkali    dibasic phosphate and alkali pyrophosphate salts, e.g., alkali    phosphate salts selected from sodium phosphate dibasic, potassium    phosphate dibasic, dicalcium phosphate dihydrate, calcium    pyrophosphate, tetrasodium pyrophosphate, tetrapotassium    pyrophosphate, sodium tripolyphosphate, disodium    hydrogenorthophoshpate, monosodium phosphate, pentapotassium    triphosphate and mixtures of any of two or more of these, in an    amount of 0.1-200%, e.g., 0.1-8%, e.g., e.g., 0.2 to 5%, e.g., 0.3    to 2%, e.g., 0.3 to 1%, e.g about 0.5%, about 1%, about 2%, about    5%⁰, about 6%, by weight of the composition.-   1.50 Any of the preceding compositions comprising tetrapotassium    pyrophosphate, disodium hydrogenorthophosphate, monosodium    phosphate, and pentapotassium triphosphate.-   1.51 Any of the preceding compositions, wherein the composition    further comprises stannous pyrophosphate, wherein the stannous    pyrophosphate is from 0.1%-3% by wt. of the composition. (e.g.,    about 1% by wt. of the composition).-   1.52 Any of the preceding compositions comprising a polyphosphate.-   1.53 The composition of 1.49, wherein the polyphosphate is    tetrasodium pyrophosphate.-   1.54 The composition of 1.53, wherein the tetrasodium pyrophosphate    is from 0.1-1.0 wt % (e.g., about 0.5 wt %).-   1.55 Any of the preceding compositions further comprising a second    abrasive or particulate (e.g., silica).-   1.56 Any of the preceding compositions wherein the second abrasive    silica is synthetic amorphous silica. (e.g., 1%-28% by wt.) (e.g.,    8%-25% by wt.)-   1.57 Any of the preceding composition wherein the silica abrasives    are silica gels or precipitated amorphous silicas, e.g. silicas    having an average particle size ranging from 2.5 microns to 12    microns.-   1.58 Any of the preceding compositions further comprising a small    particle silica having a median particle size (d50) of 1-5 microns    (e.g., 3-4 microns) (e.g., about 5 wt. % Sorbosil AC43 from PQ    Chemicals, Warrington, United Kingdom).-   1.59 Any of the preceding compositions wherein 20-30 wt % of the    total silica in the composition is small particle silica (e.g.,    having a median particle size (d50) of 3-4 microns) and wherein the    small particle silica is about 5 wt. % of the oral care composition.-   1.60 Any of the preceding compositions comprising silica wherein the    silica is used as a thickening agent, e.g., particle silica.-   1.61 Any of the preceding compositions further comprising a nonionic    surfactant, wherein the nonionic surfactant is in an amount of from    0.5-5%, e.g, 1-2%, selected from poloxamers (e.g., poloxamer 407),    polysorbates (e.g., polysorbate 20), polyoxyl hydrogenated castor    oil (e.g., polyoxyl 40 hydrogenated castor oil), and mixtures    thereof.-   1.62 Any of the preceding compositions, wherein the poloxamer    nonionic surfactant has an average polyoxypropylene molecular mass    (Mw) of from 3000 to 5000 g/mol and a polyoxyethylene content of    from 60 to 80 mol %, e.g., the poloxamer nonionic surfactant    comprises poloxamer 407.-   1.63 Any of the preceding compositions further comprising glycerin,    wherein the glycerin is in a total amount of 25-40% (e.g., about    35%).-   1.64 The composition of 1.63, wherein the glycerin is in an amount    of about 35% by wt. of the composition.-   1.65 The composition of 1.63, wherein the glycerin is in an amount    of about 26% by wt. of the composition.-   1.66 Any of the preceding compositions further comprising sorbitol,    wherein the sorbitol is in a total amount of 10-40% (e.g., about    23%).-   1.67 The composition of 1.66, wherein the sorbitol is in an amount    of about 13% by wt. of the composition.-   1.68 The composition of any of 1.63-1.67, wherein the glycerin is an    amount of about 26% by wt., and the sorbitol is in an amount of    about 13% by wt.-   1.69 Any of the preceding compositions, wherein the ratio of the    amount of zinc oxide (e.g., wt. %) to zinc citrate (e.g., wt %) is    from 1.5:1 to 4.5:1 (e.g., 2:1, 2.5:1, 3:1, 3.5:1, or 4:1).-   1.70 Any of the preceding compositions, wherein the zinc citrate is    in an amount of from 0.25 to 1.0 wt % (e.g., 0.5 wt. %) and zinc    oxide may be present in an amount of from 0.75 to 1.25 wt % (e.g.,    1.0 wt. %) based on the weight of the oral care composition.-   1.71 Any of the preceding compositions wherein the zinc citrate is    about 0.5 wt %.-   1.72 Any of the preceding compositions wherein the zinc oxide is    about 1.0 wt %.-   1.73 Any of the preceding compositions where the zinc citrate is    about 0.5 wt % and the zinc oxide is about 1.0 wt %.-   1.74 Any of the preceding compositions further comprising an    additional ingredient selected from: benzyl alcohol,    Methylisothizolinone (“MIT”), Sodium bicarbonate, sodium methyl    cocoyl taurate (tauranol), lauryl alcohol, and polyphosphate.-   1.75 Any of the preceding compositions wherein the benzyl alcohol is    present from 0.1-0.6 wt %, (e.g., 0.1-0.4 wt %) e.g. about 0.1 wt.    %, about 0.2 wt. %, or about 0.3 wt. %.-   1.76 Any of the preceding compositions wherein the benzyl alcohol is    about 0.1 wt %.-   1.77 Any of the preceding compositions wherein the benzyl alcohol is    considered a preservative.-   1.78 Any of the preceding compositions comprising polymer films.-   1.79 Any of the preceding compositions comprising flavoring,    fragrance and/or coloring.-   1.80 The composition of 1.65, wherein the flavoring agent is sodium    saccharin, sucralose, or a mixture thereof.-   1.81 Any of the preceding compositions, wherein the composition    comprises a thickening agents selected from the group consisting of    carboxyvinyl polymers, xanthan gum, carrageenan, hydroxyethyl    cellulose and water soluble salts of cellulose ethers (e.g., sodium    carboxymethyl cellulose and sodium carboxymethyl hydroxyethyl    cellulose).-   1.82 Any of the preceding compositions, wherein the compositions    comprises sodium carboxymethyl cellulose (e.g., from 0.5 wt. %-1.5    wt. %).-   1.83 Any of the preceding compositions comprising from 5%-40%, e.g.,    10%-35%, e.g., about 15%, 25%, 30%, and 35% water.-   1.84 Any of the preceding compositions comprising an additional    antibacterial agent selected from halogenated diphenyl ether (e.g.    triclosan), herbal extracts and essential oils (e.g., rosemary    extract, tea extract, magnolia extract, thymol, menthol, eucalyptol,    geraniol, carvacrol, citral, honokiol, catechol, methyl salicylate,    epigallocatechin gallate, epigallocatechin, gallic acid, miswak    extract, sea-buckthorn extract), bisguanide antiseptics (e.g.,    chlorhexidine, alexidine or octenidine), quaternary ammonium    compounds (e.g., cetylpyridinium chloride (CPC), benzalkonium    chloride, tetradecylpyridinium chloride (TPC),    N-tetradecyl-4-ethylpyridinium chloride (TDEPC)), phenolic    antiseptics, hexetidine, octenidine, sanguinarine, povidone iodine,    delmopinol, salifluor, metal ions (e.g., zinc salts and zinc    compounds, for example, Zinc Chloride, Zinc Lactate, Zinc Sulfate,    Zinc Oxide, stannous salts, copper salts, iron salts), sanguinarine,    propolis and oxygenating agents (e.g., hydrogen peroxide, buffered    sodium peroxyborate or peroxycarbonate), phthalic acid and its    salts, monoperthalic acid and its salts and esters, ascorbyl    stearate, oleoyl sarcosine, alkyl sulfate, dioctyl sulfosuccinate,    salicylanilide, domiphen bromide, delmopinol, octapinol and other    piperidino derivatives, nicin preparations, chlorite salts; and    mixtures of any of the foregoing.-   1.85 Any of the preceding compositions comprising an antioxidant,    e.g., selected from the group consisting of Co-enzyme Q10, PQQ,    Vitamin C, Vitamin E, Vitamin A, BHT, anethole-dithiothione, and    mixtures thereof.-   1.86 Any of the preceding compositions comprising a whitening agent.-   1.87 Any of the preceding compositions comprising a whitening agent    selected from a whitening active selected from the group consisting    of peroxides, metal chlorites, perborates, percarbonates,    peroxyacids, hypochlorites, and combinations thereof.-   1.88 Any of the preceding compositions further comprising hydrogen    peroxide or a hydrogen peroxide source, e.g., urea peroxide or a    peroxide salt or complex (e.g., such as peroxyphosphate,    peroxycarbonate, perborate, peroxysilicate, or persulphate salts;    for example calcium peroxyphosphate, sodium perborate, sodium    carbonate peroxide, sodium peroxyphosphate, and potassium    persulfate), or hydrogen peroxide polymer complexes such as hydrogen    peroxide-polyvinyl pyrrolidone polymer complexes.-   1.89 Any of the preceding compositions further comprising an agent    that interferes with or prevents bacterial attachment, e.g., ethyl    lauryl arginate (ELA) or chitosan.-   1.90 Any of the preceding compositions comprising:    -   a. about 1.0% zinc oxide    -   b. about 0.5% zinc citrate    -   c. about 1.5% L-arginine    -   d. about 0.32% sodium fluoride;    -   e. about 3 wt. % to 15 wt. % silica abrasive which exhibits an        acid pH when measured as an aqueous slurry (e.g., prophy silica)        (e.g., Sylodent 783)-   1.91 Any of the preceding compositions comprising:    -   a. about 1.0% zinc oxide    -   b. about 0.5% zinc citrate    -   c. about 5% L-arginine    -   d. about 0.32% sodium fluoride    -   e. about 10 wt. % to 15 wt. % silica abrasive which exhibits an        acid pH when measured as an aqueous slurry (e.g., prophy silica)        (e.g., Sylodent 783), and-   1.92 Any of the preceding compositions comprising:    -   a. about 1.0% zinc oxide    -   b. about 0.5% zinc citrate    -   c. about 5% L-arginine    -   d. about 0.32% sodium fluoride;    -   e. about 3 wt. % to 15 wt. % silica abrasive which exhibits an        acid pH when measured as an aqueous slurry. (e.g., prophy        silica) (e.g., Sylodent 783)-   1.93 Any of the preceding compositions comprising a silica, wherein    the silica is Zeodent 114.-   1.94 Any of the preceding compositions effective upon application to    the oral cavity, e.g., by rinsing, optionally in conjunction with    brushing, to (i) reduce or inhibit formation of dental caries. (ii)    reduce, repair or inhibit pre-carious lesions of the enamel, e.g.,    as detected by quantitative light-induced fluorescence (QLF) or    electrical caries measurement (ECM), (iii) reduce or inhibit    demineralization and promote remineralization of the teeth, (iv)    reduce hypersensitivity of the teeth, (v) reduce or inhibit    gingivitis, (vi) promote healing of sores or cuts in the    mouth, (vii) reduce levels of acid producing bacteria, (viii) to    increase relative levels of arginolytic bacteria, (ix) inhibit    microbial biofilm formation in the oral cavity, (x) raise and/or    maintain plaque pH at levels of at least pH 5.5 following sugar    challenge, (xi) reduce plaque accumulation, (xii) treat, relieve or    reduce dry mouth, (xiii) clean the teeth and oral cavity (xiv)    reduce erosion, (xv) prevents stains and/or whiten teeth, (xvi)    immunize the teeth against cariogenic bacteria; and/or (xvii)    promote systemic health, including cardiovascular health, e.g., by    reducing potential for systemic infection via the oral tissues.-   1.95 Any of the preceding oral compositions, wherein the oral    composition may be any of the following oral compositions selected    from the group consisting of: a toothpaste or a dentifrice, a    mouthwash or a mouth rinse, a topical oral gel, and a denture    cleanser.-   1.96 A composition obtained or obtainable by combining the    ingredients as set forth in any of the preceding compositions.-   1.97 A composition obtained or obtainable by combining the    ingredients as set forth in any of the preceding compositions.-   1.98 A composition for use as set for in any of the preceding    compositions.

In another embodiment, the invention encompasses a method to improveoral health comprising applying an effective amount of the oralcomposition of any of the embodiments set forth above (e.g., any ofComposition 1.0 et seq) to the oral cavity of a subject in need thereof,e.g.,

-   -   i. a method to reduce or inhibit formation of dental caries,        reduce, repair or inhibit early enamel lesions, e.g., as        detected by quantitative light-induced fluorescence (QLF) or        electrical caries measurement (ECM),    -   ii. reduce or inhibit demineralization and promote        remineralization of the teeth,    -   iii. reduce hypersensitivity of the teeth,    -   iv. reduce or inhibit gingivitis,    -   v. promote healing of sores or cuts in the mouth,    -   vi. reduce levels of acid producing bacteria,    -   vii. to increase relative levels of arginolytic bacteria,    -   viii. inhibit microbial bio film formation in the oral cavity,    -   ix. raise and/or maintain plaque pH at levels of at least pH 5.5        following sugar challenge,    -   x. reduce plaque accumulation,    -   xi. treat dry mouth,    -   xii. enhance systemic health, including cardiovascular        health,e.g., by reducing potential for systemic infection via        the oral tissues,    -   xiii. Whiten teeth,    -   xiv. reduce erosion of the teeth,    -   xv. immunize (or protect) the teeth against cariogenic bacteria        and their effects, and/or    -   xvi. clean the teeth and oral cavity.

In some embodiments, the present invention further comprises the use ofsodium bicarbonate, sodium methyl cocoyl taurate (tauranol),methylisothiazolinone, and benzyl alcohol and combinations thereof inthe manufacture of a Composition of the Invention, e.g., for use in anyof the indications set forth in the above method of Composition 1.0, etseq.

DETAILED DESCRIPTION

As used herein, the terms “oral composition” and “oral care composition”mean the total composition that is delivered to the oral surfaces. Thecomposition is further defined as a product which, during the normalcourse of usage, is not, intended for systemic administration ofparticular therapeutic agents or intentionally swallowed; but rather, isretained in the oral cavity for a time sufficient to contactsubstantially all of the dental surfaces and/or oral tissues for thepurposes of oral activity. Examples of such compositions include, butare not limited to, toothpaste or a dentifrice, a mouthwash or a mouthrinse, a topical oral gel, a denture cleanser, and the like.

As used herein, the term “dentifrice” means paste, gel, or liquidformulations unless otherwise specified. The dentifrice composition canbe in any desired form such as deep striped, surface striped,multi-layered, having the gel surrounding the paste, or any combinationthereof. Alternatively the oral composition is provided as a dual phasecomposition, wherein individual compositions are combined when dispensedfrom a separated compartment dispenser.

Basic Amino Acids

The basic amino acids which can be used in the compositions and methodsof the invention include not only naturally occurring basic amino acids,such as arginine, lysine, and histidine, but also any basic amino acidshaving a carboxyl group and an amino group in the molecule, which arewater-soluble and provide an aqueous solution with a pH of 7 or greater.

Accordingly, basic amino acids include, but are not limited to,arginine, lysine, serine, citrullene, ornithine, creatine, histidine,diaminobutanoic acid, diaminoproprionic acid, salts thereof orcombinations thereof. In a particular embodiment, the basic amino acidsare selected from arginine, citrullene, and ornithine.

In certain embodiments, the basic amino acid is arginine, for example,L-arginine, or a salt thereof.

The compositions of the invention are intended for topical use in themouth and so salts for use in the present invention should be safe forsuch use, in the amounts and concentrations provided. Suitable saltsinclude salts known in the art to be pharmaceutically acceptable saltswhich are generally considered to be physiologically acceptable in theamounts and concentrations provided. Physiologically acceptable saltsinclude those derived from pharmaceutically acceptable inorganic ororganic acids or bases, for example acid addition salts formed by acidswhich form a physiological acceptable anion, e.g., hydrochloride orbromide salt, and base addition salts formed by bases which form aphysiologically acceptable cation, for example those derived from alkalimetals such as potassium and sodium or alkaline earth metals such ascalcium and magnesium. Physiologically acceptable salts may be obtainedusing standard procedures known in the art, for example, by reacting asufficiently basic compound such as an amine with a suitable acidaffording a physiologically acceptable anion.

Fluoride Ion Source

The oral care compositions may further include one or more fluoride ionsources, e.g., soluble fluoride salts. A wide variety of fluorideion-yielding materials can be employed as sources of soluble fluoride inthe present compositions. Examples of suitable fluoride ion-yieldingmaterials are found in U.S. Pat. No. 3,535,421, to Briner et al.; U.S.Pat. No. 4,885,155, to Parran, Jr. et al. and U.S. Pat. No. 3,678,154,to Widder et al., each of which are incorporated herein by reference.Representative fluoride ion sources used with the present invention(e.g., Composition 1.0 et seq.) include, but are not limited to,stannous fluoride, sodium fluoride, potassium fluoride, sodiummonofluorophosphate, sodium fluorosilicate, ammonium fluorosilicate,amine fluoride, ammonium fluoride, and combinations thereof. In certainembodiments the fluoride ion source includes stannous fluoride, sodiumfluoride, sodium monofluorophosphate as well as mixtures thereof. Wherethe formulation comprises calcium salts, the fluoride salts arepreferably salts wherein the fluoride is covalently bound to anotheratom, e.g., as in sodium monofluorophosphate, rather than merelyionically bound, e.g., as in sodium fluoride.

Surfactants

The invention may in some embodiments contain anionic surfactants, e.g.,the Compositions of Composition 1.0, et seq., for example, water-solublesalts of higher fatty acid monoglyceride monosulfates, such as thesodium salt of the monosulfated monoglyceride of hydrogenated coconutoil fatty acids such as sodium N-methyl N-cocoyl taurate, sodiumcoco-glyceride sulfate; higher alkyl sulfates, such as sodium laurylsulfate; higher alkyl-ether sulfates, e.g., of formulaCH₃(CH₂)_(m)CH₂(OCH₂CH₂)_(n)OSO₃X, wherein m is 6-16, e.g., 10, n is1-6, e.g., 2, 3 or 4, and X is Na or, for example sodium laureth-2sulfate (CH₃(CH₂)₁₀CH₂(OCH₂CH₂)₂OSO₃Na); higher alkyl aryl sulfonatessuch as sodium dodecyl benzene sulfonate (sodium lauryl benzenesulfonate); higher alkyl sulfoacetates, such as sodium laurylsulfoacetate (dodecyl sodium sulfoacetate), higher fatty acid esters of1,2 dihydroxy propane sulfonate, sulfocolaurate (N-2-ethyl lauratepotassium sulfoacetamide) and sodium lauryl sarcosinate. By “higheralkyl” is meant, e.g., C₆₋₃₀ alkyl. In particular embodiments, theanionic surfactant (where present) is selected from sodium laurylsulfate and sodium ether lauryl sulfate. When present, the anionicsurfactant is present in an amount which is effective, e.g., >0.001% byweight of the formulation, but not at a concentration which would beirritating to the oral tissue, e.g., 1%, and optimal concentrationsdepend on the particular formulation and the particular surfactant. Inone embodiment, the anionic surfactant is present at from 0.03% to 5% byweight, e.g., 1.5%.

Cationic surfactants useful in the present invention can be broadlydefined as derivatives of aliphatic quaternary ammonium compounds havingone long alkyl chain containing 8 to 18 carbon atoms such as lauryltrimethylammonium chloride, cetyl pyridinium chloride, cetyltrimethylammonium bromide, di-isobutylphenoxyethyldimethylbenzylammoniumchloride, coconut alkyltrimethylammonium nitrite, cetyl pyridiniumfluoride, and mixtures thereof. Illustrative cationic surfactants arethe quaternary ammonium fluorides described in U.S. Pat. No. 3,535,421,to Briner et al., herein incorporated by reference. Certain cationicsurfactants can also act as germicides in the compositions.

Illustrative nonionic surfactants of Composition 1.0, et seq., that canbe used in the compositions of the invention can be broadly defined ascompounds produced by the condensation of alkylene oxide groups(hydrophilic in nature) with an organic hydrophobic compound which maybe aliphatic or alkylaromatic in nature. Examples of suitable nonionicsurfactants include, but are not limited to, the Pluronics, polyethyleneoxide condensates of alkyl phenols, products derived from thecondensation of ethylene oxide with the reaction product of propyleneoxide and ethylene diamine, ethylene oxide condensates of aliphaticalcohols, long chain tertiary amine oxides, long chain tertiaryphosphine oxides, long chain dialkyl sulfoxides and mixtures of suchmaterials. In a particular embodiment, the composition of the inventioncomprises a nonionic surfactant selected from polaxamers (e.g.,polaxamer 407), polysorbates (e.g., polysorbate 20), polyoxylhydrogenated castor oils (e.g., polyoxyl 40 hydrogenated castor oil),and mixtures thereof.

Illustrative amphoteric surfactants of Composition 1.0, et seq., thatcan be used in the compositions of the invention include betaines (suchas cocamidopropylbetaine), derivatives of aliphatic secondary andtertiary amines in which the aliphatic radical can be a straight orbranched chain and wherein one of the aliphatic substituents containsabout 8-18 carbon atoms and one contains an anionic water-solubilizinggroup (such as carboxylate, sulfonate, sulfate, phosphate orphosphonate), and mixtures of such materials.

Illustrative zwitterionic surfactants of Composition 1.0, el seq., thatcan be used in the compositions of the invention include derivatives ofaliphatic quaternary ammonium, phosphonium and sulfonium compounds inwhich the aliphatic radical can be a straight or branched chain andwherein one of the aliphatic substituents contains about 8-18 carbonatoms and one contains an anionic water-solubilizing group (such ascarboxy, sulfonate, sulfate, phosphate or phosphonate). The surfactantor mixtures of compatible surfactants can be present in the compositionsof the present invention in 0.1% to 5%, in another embodiment 0.3% to 3%and in another embodiment 0.5% to 2% by weight of the total composition.

Flavoring Agents

The oral care compositions of the invention may also include a flavoringagent. Flavoring agents which are used in the practice of the presentinvention include, but are not limited to, essential oils and variousflavoring aldehydes, esters, alcohols, and similar materials, as well assweeteners such as sodium saccharin. Examples of the essential oilsinclude oils of spearmint, peppermint, wintergreen, sassafras, clove,sage, eucalyptus, marjoram, cinnamon, lemon, lime, grapefruit, andorange. Also useful are such chemicals as menthol, carvone, andanethole. Certain embodiments employ the oils of peppermint andspearmint.

The flavoring agent is incorporated in the oral composition at aconcentration of 0.01 to 1% by weight.

Chelating and Anti-Calculus Agents

The oral care compositions of the invention (e.g., Composition 1.0 etseq) also may include one or more chelating agents able to complexcalcium found in the cell walls of the bacteria. Binding of this calciumweakens the bacterial cell wall and augments bacterial lysis.

Another group of agents suitable for use as chelating or anti-calculusagents in the present invention are the soluble pyrophosphates. Thepyrophosphate salts used in the present compositions can be any of thealkali metal pyrophosphate salts. In certain embodiments, salts includetetra alkali metal pyrophosphate, dialkali metal diacid pyrophosphate,trialkali metal monoacid pyrophosphate and mixtures thereof, wherein thealkali metals are sodium or potassium. The salts are useful in boththeir hydrated and unhydrated forms. An effective amount ofpyrophosphate salt useful in the present composition is generally enoughto provide least 0.1 wt. % pyrophosphate ions, e.g., 0.1 to 3 wt. %,e.g., 0.1 to 2 wt. %, e.g., 0.1 to 1 wt. %, e.g., 0.2 to 0.5 wt. %. Thepyrophosphates also contribute to preservation of the compositions bylowering the effect of water activity.

Polymers

The oral care compositions of the invention (e.g., Composition 1.0, etseq) also optionally include one or more polymers, such as polyethyleneglycols, polyvinyl methyl ether maleic acid copolymers, polysaccharides(e.g., cellulose derivatives, for example carboxymethyl cellulose, orpolysaccharide gums, for example xanthan gum or carrageenan gum). Acidicpolymers, for example polyacrylate gels, may be provided in the form oftheir free acids or partially or fully neutralized water soluble alkalimetal (e.g., potassium and sodium) or ammonium salts. Certainembodiments include 1:4 to 4:1 copolymers of maleic anhydride or acidwith another polymerizable ethylenically unsaturated monomer, forexample, methyl vinyl ether (methoxyethylene) having a molecular weight(M.W.) of about 30,000 to about 1,000,000. These copolymers areavailable for example as Gantrez AN 139 (M.W. 500,000), AN 1 19 (M.W.250,000) and S-97 Pharmaceutical Grade (M.W. 70,000), of GAF ChemicalsCorporation.

Other operative polymers include those such as the 1:1 copolymers ofmaleic anhydride with ethyl acrylate, hydroxyethyl methacrylate,N-vinyl-2-pyrollidone, or ethylene, the latter being available forexample as Monsanto EMA No. 1 103, M.W. 10,000 and EMA Grade 61, and 1:1copolymers of acrylic acid with methyl or hydroxyethyl methacrylate,methyl or ethyl acrylate, isobutyl vinyl ether or N-vinyl-2-pyrrolidone.

Suitable generally, are polymerized olefinically or ethylenicallyunsaturated carboxylic acids containing an activated carbon-to-carbonolefinic double bond and at least one carboxyl group, that is, an acidcontaining an olefinic double bond which readily functions inpolymerization because of its presence in the monomer molecule either inthe alpha-beta position with respect to a carboxyl group or as part of aterminal methylene grouping. Illustrative of such acids are acrylic,methacrylic, ethacrylic, alpha-chloroacrylic, crotonic, beta-acryloxypropionic, sorbic, alpha-chlorosorbic, cinnamic, beta-styrylacrylic,muconic, itaconic, citraconic, mesaconic, glutaconic, aconitic,alpha-phenylacrylic, 2-benzyl acrylic, 2-cyclohexylacrylic, angelic,umbellic, fumaric, maleic acids and anhydrides. Other different olefinicmonomers copolymerizable with such carboxylic monomers includevinylacetate, vinyl chloride, dimethyl maleate and the like. Copolymerscontain sufficient carboxylic salt groups for water-solubility.

A further class of polymeric agents includes a composition containinghomopolymers of substituted acrylamides and/or homopolymers ofunsaturated sulfonic acids and salts thereof, in particular wherepolymers are based on unsaturated sulfonic acids selected fromacrylamidoalykane sulfonic acids such as 2-acrylamide 2 methylpropanesulfonic acid having a molecular weight of about 1,000 to about2,000,000, described in U.S. Pat. No. 4,842,847, Jun. 27, 1989 to Zahid,incorporated herein by reference.

Another useful class of polymeric agents includes polyamino acids,particularly those containing proportions of anionic surface-activeamino acids such as aspartic acid, glutamic acid and phosphoserine, asdisclosed in U.S. Pat. No. 4,866,161 Sikes et al., incorporated hereinby reference.

In preparing oral care compositions, it is sometimes necessary to addsome thickening material to provide a desirable consistency or tostabilize or enhance the performance of the formulation. In certainembodiments, the thickening agents are carboxyvinyl polymers,carrageenan, xanthan gum, hydroxyethyl cellulose and water soluble saltsof cellulose ethers such as sodium carboxymethyl cellulose and sodiumcarboxymethyl hydroxyethyl cellulose. Natural gums such as karaya, gumarabic, and gum tragacanth can also be incorporated. Colloidal magnesiumaluminum silicate or finely divided silica can be used as component ofthe thickening composition to further improve the composition's texture.In certain embodiments, thickening agents in an amount of about 0.5% toabout 5.0% by weight of the total composition are used.

Abrasives

Generally, the inclusion of abrasives in dentifrice formulations isnecessary for effective cleaning of teeth by brushing. It has beendetermined that by including an abrasive silica having an acid pH in thecomposition, compositions of enhanced viscosity stability are obtained.Prophy silica available from Grace, offered as Sylodent™, can be usedwith various embodiments of the present invention (e.g., Composition 1.0el seq).

The acidic silica abrasive is included in the dentifrice components at aconcentration of about 2 to about 35% by weight; about 3 to about 20% byweight, about 3 to about 15% by weight, about 10 to about 15% by weight.For example, the acidic silica abrasive may be present in an amountselected from 2 wt. %, 3 wt. %, 4 wt. %, 5 wt. %, 6 wt. %, 7 wt. %, 8wt. %, 9 wt. %, 10 wt. %, 11 wt. %, 12 wt. %, 13 wt. %, 14 wt. %, 15 wt.%, 16 wt. %, 17 wt. %, 18 wt. %, 19 wt. %, 20 wt. %.

A commercially available acidic silica abrasive is Sylodent 783available from W. R. Grace & Company, Baltimore, Md. Sylodent 783 has apH of 3.4-4.2 when measured as a 5% by weight slurry in water. For usein the present invention, the silica material has an average particlesize of less than 10 microns, e.g., 3-7 microns, e.g. about 5.5 microns.For example a small particle silica may have an average particle size(D50) of 2.5-4.5 microns.

The composition may also include any silica suitable for oral carecompositions, such as precipitated silicas or silica gels. For examplesynthetic amorphous silica. Silica may also be available as a thickeningagent, e.g., particle silica. For example, the silica can also be smallparticle silica (e.g., Sorbosil AC43 from PQ Corporation, Warrington,United Kingdom). However the additional abrasives are preferably notpresent in a type or amount so as to increase the RDA of the dentifriceto levels which could damage sensitive teeth, e.g., greater than 130.

The invention may also comprise a commercially available cleaning silicain certain embodiments of the invention (e.g., any of Composition 1.0,el seq). Zeodent 114 offered by J. M. Huber Finland Oy Telakkatie 5FIN-49460 Hamina, is one such commercially available silica.

Water

Water is present in the oral compositions of the invention. Water,employed in the preparation of commercial oral compositions should bedeionized and free of organic impurities. Water commonly makes up thebalance of the compositions and includes 5% to 45%, e.g., 10% to 20%,e.g., 25-35%, by weight of the oral compositions. This amount of waterincludes the free water which is added plus that amount which isintroduced with other materials such as with sorbitol or silica or anycomponents of the invention. The Karl Fischer method is a one measure ofcalculating free water.

Humectants

Within certain embodiments of the oral compositions (e.g., Composition1.0 el seq), it is also desirable to incorporate a humectant to reduceevaporation and also contribute towards preservation by lowering wateractivity. Certain humectants can also impart desirable sweetness orflavor to the compositions. The humectant, on a pure humectant basis,generally includes 15% to 70% in one embodiment or 30% to 65% in anotherembodiment by weight of the composition.

Suitable humectants include edible polyhydric alcohols such as glycerin,sorbitol, xylitol, propylene glycol as well as other polyols andmixtures of these humectants. Mixtures of glycerin and sorbitol may beused in certain embodiments as the humectant component of thecompositions herein.

The present invention in its method aspect involves applying to the oralcavity a safe and effective amount of the compositions described herein.

The compositions and methods according to the invention (e.g.,Composition 1.0 et seq) can be incorporated into oral compositions forthe care of the mouth and teeth such as toothpastes, transparent pastes,gels, mouth rinses, sprays and chewing gum.

In some embodiments, the present invention provides an oral carecomposition comprising: a basic amino acid in free or salt wherein theamino acid is selected from arginine, lysine, and a combination thereof;a combination of zinc ion sources; and a thickening system comprising:from about 0.5 wt. % to about 2 wt. % of a nonionic cellulose ether; andfrom about 0.1 wt. % to about 1 wt. % of a polysaccharide gum. In someembodiments, the present invention provides an oral care compositioncomprising: a basic amino acid in free or salt wherein the amino acid isselected from arginine, lysine, and a combination thereof: a combinationof zinc ion sources; and a thickening system comprising: from about 0.5wt. % to about 1 wt. % of a nonionic cellulose ether; and from about0.25 wt. % to about 0.75 wt. % of a polysaccharide gum.

Some embodiments provide compositions comprising a nonionic celluloseether having a molecular weight of about 300,000 to about 350,000. Otherembodiments provide compositions comprising a nonionic cellulose etherhaving a molecular weight of about 300,000. While other embodimentsprovide compositions comprising a nonionic cellulose ether having amolecular weight of about 350,000 (e.g. such as Tylose variantsavailable SE Tylose GmbH & Co. KG).

In some embodiments, the nonionic cellulose ether compriseshydroxyethylcellulose. In further embodiments, the oral care compositioncomprises from about 0.5 wt. % to about 1 wt. % ofhydroxyethylcellulose. Still further embodiments provide oral carecompositions comprising from about 0.6 wt. % to about 0.8 wt. % ofhydroxyethylcellulose. Yet other embodiments provide oral carecompositions comprising about 0.5 wt. %, about 0.6 wt. %, about 0.7 wt.%, about 0.8 wt. %, about 0.9 wt. % or about 1 wt. % ofhydroxyethylcellulose. Some embodiments provide oral care compositionscomprising 0.5 wt. %, 0.6 wt. %, 0.7 wt. %, 0.8 wt. %, 0.9 wt. % or 1wt. % of hydroxyethylcellulose.

In some embodiments, the hydroxyethylcellulose has a viscosity, measuredat 2% in water at 25° C., of about 150 to about 400 cps. In someembodiments, the hydroxyethylcellulose having a viscosity, measured at2% in water at 25° C., of about 150 to about 400 cps at 25° C. ispresent in an amount of from about 0.5 wt. % to about 1 wt. %. Someembodiments provide oral care compositions comprising 0.5 wt. %, 0.6 wt.%, 0.7 wt. %, 0.8 wt. %, 0.9 wt. % or 1 wt. % of a hydroxyethylcellulosehaving a viscosity, measured at 2% in water at 25° C., of about 150 toabout 400 cps.

Some embodiments provide oral care compositions comprisinghydroxyethylcellulose having a molecular weight of about 300,000 orabout 350,000, in the amount of from about 0.5 wt. % to about 1 wt. %.Other embodiments provide oral care compositions comprising 0.5 wt. %,0.6 wt. %, 0.7 wt. %, 0.8 wt. %, 0.9 wt. % or 1 wt. % of ahydroxyethylcellulose having a molecular weight of about 300,000.Certain embodiments provide oral care compositions comprising 0.5 wt. %,0.6 wt. %, 0.7 wt. %, 0.8 wt. %, 0.9 wt. % or 1 wt. % of ahydroxyethylcellulose having a molecular weight of about 350,000.

In some embodiments, the polysaccharide gum is xanthan gum. In someembodiments, the oral care composition comprises from about 0.1 wt. % toabout 1 wt. % of xanthan gum. In some embodiments, the oral carecomposition comprises from about 0.2 wt. % to about 0.9 wt. % of xanthangum. In some embodiments, the oral care composition comprises from about0.25 wt. % to about 0.75 wt. % of xanthan gum. In some embodiments, theoral care composition comprises from about 0.3 wt. % to about 0.7 wt. %of xanthan gum. In some embodiments, the oral care composition comprisesabout 0.3 wt. % about 0.4 wt. %, about 0.5 wt. %, about 0.6 wt. % orabout 0.7 wt. % of xanthan gum.

In some embodiments, the present invention provides an oral carecomposition comprising: a basic amino acid in free or salt wherein theamino acid is selected from arginine, lysine, and a combination thereof;a combination of zinc ion sources; and a thickening system comprising:from about 0.5 wt. % to about 1 wt. % of a nonionic cellulose ether; andfrom about 0.25 wt. % to about 0.75 wt. % of a polysaccharide gum.

In some embodiments, the present invention provides an oral carecomposition comprising: a basic amino acid in free or salt wherein theamino acid is selected from arginine, lysine, and a combination thereof;a combination of zinc ion sources; and a thickening system comprising:from about 0.6 wt. % to about 0.8 wt. % of a nonionic cellulose ether;and from about 0.7 wt. % to about 0.8 wt. % of a polysaccharide gum.

In some embodiments, the thickening system further comprises from about5 wt. % to about 10 wt. % silica. In some embodiments, the thickeningsystem comprises from about 0.5 wt. % to about 15 wt. % of the oral carecomposition.

In certain embodiments, the hydroxyethylcellulose and the polysaccharidegum are present in a weight ratio of from about 8:1 to about 1:10. Inother embodiments, the hydroxyethylcellulose and the polysaccharide gumare present in a weight ratio of from about 4:1 to about 1:2. Yet otherembodiments provide compositions wherein the hydroxyethylcellulose andthe polysaccharide gum are present in a weight ratio of from about 3:1to about 1:1.

In some embodiments, the oral care composition further comprises afluoride ion source selected from sodium fluoride, sodiummonofluorophosphate, and stannous fluoride.

In some embodiments, the oral care composition comprises about 1.0 wt. %zinc oxide; about 0.5 wt. % zinc citrate; about 1.5 wt. % L-arginine;from about 0.3 wt. % to about 0.8 wt. % of xanthan gum; and from about0.5 wt. % to about 1 wt. % of hydroxyethylcellulose. Some embodimentscomprise from about 0.3 wt. % to about 0.6 wt. % of xanthan gum.

In further embodiments, the oral care composition loses no more thanabout 45% of its initial viscosity after one year. In some embodiments,the oral care composition loses no more than about 40% of its initialviscosity after one year. In other embodiments, the oral carecomposition loses no more than about 35% of its initial viscosity afterone year. In yet other embodiments, the oral care composition loses nomore than about 30% of its initial viscosity after one year. In someembodiments, the oral care composition loses no more than about 25%,24%, 23%, 22%, 21% or 20% of its initial viscosity after one year.

In some embodiments, the oral care composition has a G′/G″ ratio ofgreater than 0.5. In some embodiments, the oral care composition has aG′/G″ ratio of greater than 0.75. In some embodiments, the oral carecomposition has a G′/G″ ratio of greater than 1. In some embodiments,the oral care composition has a G′/G″ ratio of greater than 1.5. In someembodiments, the oral care composition has a G′/G″ ratio of less than 2.In some embodiments, the oral care composition has a G′/G″ ratio of lessthan 1.5. In some embodiments, the oral care composition has a G′/G″ratio of less than 1. Methods of quantifying the elastic modulus (G′),the loss modulus (G″) and G′/G″ ratios are described, for example, in WO2013/089734 A1, the contents of which are hereby incorporated herein byreference in their entirety.

In some embodiments, the compositions of the present invention provide aconsistency, K, less than 30 Pa*s^(n). In some embodiments, thecompositions of the present invention provide a flow index, n, ofgreater than 0.3. In some embodiments, the compositions of the presentinvention provide a consistency, K, less than 30 Pa*s^(n) and a flowindex, n, of greater than 0.3. In some embodiments, the compositions ofthe present invention provide a consistency, K, less than 30 Pa*s^(n); aflow index, n, of greater than 0.3; and a G′/G″ ratio of less than 2. Insome embodiments, the compositions of the present invention provide aflow index, n, of greater than 0.3; and a G′/G″ ratio of less than 2. Insome embodiments, the compositions of the present invention provide aconsistency, K, less than 30 Pa*s^(n); and a G′/G″ ratio of less than 2.

In some embodiments, the oral care compositions of the present inventionprovide a yield stress greater than 25 Pa. In other embodiments, theoral care compositions of the present invention provide a yield stressgreater than 30 Pa. Yet further embodiments, provide oral carecompositions that demonstrate a yield stress greater than 35 Pa.

As used throughout, ranges are used as shorthand for describing each andevery value that is within the range. Any value within the range can beselected as the terminus of the range. In addition, all references citedherein are hereby incorporated by reference in their entireties. In theevent of a conflict in a definition in the present disclosure and thatof a cited reference, the present disclosure controls. It is understoodthat when formulations are described, they may be described in terms oftheir ingredients, as is common in the art, notwithstanding that theseingredients may react with one another in the actual formulation as itis made, stored and used, and such products are intended to be coveredby the formulations described.

The following examples further describe and demonstrate illustrativeembodiments within the scope of the present invention. The examples aregiven solely for illustration and are not to be construed as limitationsof this invention as many variations are possible without departing fromthe spirit and scope thereof.

EXAMPLES Example 1

The examples herein detail how the viscosity over time for a compositionwhich exhibits a problem of rapid reduction in viscosity (Run A), iscompared to five compositions which show the stabilized viscosityprovided by the invention (Compositions 1-5 in Table 1).

Viscosity is measured on a Brookfield HADV2 viscometer using a V74 vanespindle. This viscometer applies a user-controlled angular velocity tothe spindle, typically measured in rotations per second (RPM), andreports torque on the shaft of the spindle. Viscosity is then calculatedfrom RPM and torque as explained in the Brookfield Manual (OperatingInstructions) using too conversion parameters SRC (shear rate constant)and SMC (spindle multiplier constant). The conversion parameters aredefined as follows: SMC=290, SRC=0.2723. The test is performed at roomtemperature, and varies between 22 and 25° C. During the test, RPM ofthe spindle is swept from 200 to 0.5 in 12 steps, 10 seconds per step.The viscosity reading reported is taken at RPM=1.

Compositions containing zinc oxide, zinc citrate, arginine and afluoride source are prepared as described in Table 1, below. Allcompositions are formulated to provide a 10% pH of 8-8.5 using 0-0.35%phosphoric acid. The composition identified as Run A does not contain asilica abrasive which exhibits an acid pH when measured as an aqueousslurry. The compositions identified as Compositions 1-5 in Table 1(below) contain a silica abrasive which exhibits an acid pH (ProphySilica—Sylodent 783) when measured as an aqueous slurry in varyingamounts, as detailed below.

TABLE 1 Dentifrice Formulations Experiment ID INGREDIENTS Run AComposition 1 Composition 2 Composition 3 Composition 4 Composition 599.0%-101.0% 35 35 35 35 35 35 GLYCERIN - USP, EP VEG DEMINERALIZED Q.S.Q.S. Q.S. Q.S. Q.S. Q.S. WATER PROPHY 0 15 10 5 5 3 SILICA (SYLODENT783) ABRASIVES (e.g., 20 5 10 15 15 17 includes Abrasive silcas, HighCleaning Silicas) SILICA- 6.5 7 7 7 7 7 THICKENER ANIONIC 2 2 2 2 2 2SURFACTANT L-ARGININE 1.5 1.5 1.5 1.5 1.5 1.5 AMPHOTERIC 1.25 1.25 1.251.25 1.25 1.25 SURFACTANT NON-IONIC 0.75 0.75 0.75 0.75 0.75 0.75SURFACTANT ZINC OXIDE 1 1 1 1 1 1 POLYMER 1 1.3 1.3 1.3 1.3 1.3 COLORANT0.75 0.75 0.75 0.75 0.75 0.75 ALKALI 0.5 0.5 0.5 0.5 0.5 0.5 PHOSPHATESALT ZINC 0.5 0.5 0.5 0.5 0.5 0.5 CITRATE TRIHYDRATE PRESERVATIVE 0.40.4 0.4 0.4 0.4 0.4 SODIUM 0.32 0.32 0.32 0.32 0.32 0.32 FLUORIDE - USP,EP 85% SYRUPY 0.35 0 0 0 0 0 PHOSPHORIC ACID - FOOD GRADE FLAVORING 2 22 2 1.82 1.52 AGENT TOTAL 100 100 100 100 100 100 COMPONENTS

The composition identified as Run A displays an initial viscosity whichis initially 500,000 cps to 600,000 cps high, but decreases to under400,000 cps in 2 weeks, and under 200,000 cps at 6 weeks. Surprisingly,the compositions containing a silica abrasive which exhibits an acid pH(Prophy Silica—Sylodent 783) when measured as an aqueous slurry,Compositions 1 to 5 in Table 1 (above), eliminate this undesirablecharacteristic and instead produce viscosities that are stable orincrease over time (See, Table 2 below).

TABLE 2 Viscosity data Experiment ID Run A Composition 1 Composition 2Composition 3 Composition 4 Composition 5 Time Viscosity (cps) 0 491040363489  1 d 539119 211912 300155 272475  5 d 601597 309816  1 wk 627362288561 383245 371651  2 wk 433485 340733 328495 403212 364565  3 wk343310 314325 334292  4 wk 224794 395483 304019 430909 423823  5 wk375515 338801 322698  6 wk 193233 376804 344598 334292 406432 442503  7wk 334292  9 wk 387753 10 wk 351039 364565 11 wk 158451 373583 381956 12wk 405788 357480 13 wk 405788 398059 393550

Upon further investigation, it was found that the silica abrasive whichexhibits an acid pH when measured as an aqueous slurry silica is acidic(pH 3.4-4.2) does not require phosphoric acid to adjust the product pH.Other abrasive silicas and high cleaning silicas are about neutral in pH(pH 7-8) and thus, require phosphoric acid for pH adjustment.

TABLE 3 Composition 6 Composition 7 Composition 8 Demineralized WaterQ.S. Q.S. Q.S. Glycerin - 99.5% 35 35 35 Polymer 1.2 1.2 1.2 Zinc Oxide1 1 1 Zinc Citrate 0.5 0.5 0.5 Alkali Phosphate Salt 0.5 0.5 0.5Flavoring agent 1.82 1.82 1.82 Sodium Fluoride 0.32 0.32 0.32 Colorant0.75 0.75 0.75 L-Arginine 1.5 1.5 1.5 Non-Ionic Surfactant 0.5 0.5 0.5Abrasives (e.g., 8 10 12 includes Abrasive Silcas, High CleaningSilicas) Prophy silica 7 5 3 (Sylodent 783) Silica - thickener 7 7 8.5Preservative 0.4 0.4 0.4 Anionic Surfactant 5.7 5.7 5.7 AmphotericSurfactant 1.25 1.25 1.25 Total Components 100 100 100

Upon further investigation, when phosphoric acid is removed from furtherformulations (Compositions 6-8 in Table 3, above), they demonstrateimprovement in viscosity stability, and this viscosity trend remainedrelatively stable from day 1 to 4 weeks when tested at: roomtemperature, 40° C. and 49° C. The data is further detailed in Table 4below.

TABLE 4 Composition 6 Composition 7 Composition 8 Viscosity, 10³ cpsViscosity, 10³ cps Viscosity, 10³ cps RT 40° C. 49° C. RT 40° C. 49° C.RT 40° C. 49° C. 0 471 324 336 0.14 370 197 268 1 363 418 390 200 227258 230 256 263 2 360 430 440 201 243 269 220 250 258 3 325 205 246 245228 277 274 4 314 412 385 224 253 253 227 268 272 6 327 218 233

Example 2

Table 5 (below) describes the formulas of three exemplary compositionsof the present invention (Compositions 9, 10 and 11) and a comparativeexample (Comparative Example 1).

TABLE 5 Composition Composition Comparative Composition 9 10 11 ExampleI Ingredient Wt % GLYCERIN 35.00000 26.00000 26.00000 35.00000SORBITOL - NON- — 13.00000 13.00000 — CRYSTAL - 70% SOLN EP PURIFIEDWATER 30.90474 27.82474 27.62474 30.84874 STANDARD ABRASIVE 10.0000010.00000 10.00000 10.00000 SILICA SILICA-THICKENER 7.00000 6.000006.00000 7.00000 SMALL PARTICLE 5.00000 5.00000 5.00000 5.00000 SILICALAURYL SULFATE 2.10526 2.10526 2.10526 2.10526 GRANULES Flavor 1.500001.50000 1.50000 1.50000 L-ARGININE 1.50000 1.50000 1.50000 1.50000COCAMIDOPROPYL 1.25000 1.25000 1.25000 1.25000 BETAINE ZINC OXIDE1.00000 1.00000 1.00000 1.00000 TITANIUM DIOXIDE 0.75000 0.75000 0.75000— XANTHAN GUM 0.60000 0.30000 0.30000 0.40000 SODIUM CMC - TYPE — — —1.10000 12 HYDROXYETHYL- 0.50000 0.80000 1.00000 — CELLULOSE (HEC)*TETRASODIUM 0.50000 0.50000 0.50000 0.50000 PYROPHOSPHATE ZINC CITRATE0.50000 0.50000 0.50000 0.50000 TRIHYDRATE POLOXAMER 407 0.50000 0.500000.50000 0.50000 BENZYL ALCOHOL 0.40000 0.40000 0.40000 0.40000 85%PHOSPHORIC 0.35000 0.35000 0.35000 0.35000 ACID SODIUM FLUORIDE -0.32000 0.32000 0.32000 0.32000 USP, EP Sweeteners 0.32000 0.400000.40000 0.42000 Additional Colorants — — — 0.30600 *HEC having amolecular weight of about 350,000

Example 3

Table 6 (below) describes the results of viscosity and static yieldstress evaluations performed on an exemplary composition of the presentinvention and a reference formula.

Viscosity and Yield Stress are measured on a Brookfield HADV2 viscometerusing V74 vane spindle 1.176 cm in length and 0.589 cm in diameter. Thisviscometer applies a user-controlled angular velocity to the spindle,typically measured in rotations per second (RPM), and reports torque, T%, measured in the percentage of the maximum total torque on the shaftof the spindle. The torque, T, measured in SI units, N*m, is related toT % as reported by the above mentioned viscometer as T=1.437*10⁻⁵*T %.

The tests are performed at room temperature (22 to 25° C.). During thetest 0.5 RPM of the spindle is first rotated for 400 sec and then RPM isswept from 0.5 to 200 and back to 0.5 in 12 logarithmical steps eachway, 10 seconds per step. The viscosity reading is taken at RPM=1 on thedecreasing RPM sweep. Viscosity is then calculated from RPM and T asexplained in the Brookfield Manual (Operating Instructions) using twoconversion parameters SRC (shear rate constant) and SMC (spindlemultiplier constant). In this case, the conversion parameters aredefined as follows: SMC=290, SRC=0.27.

Static Yield Stress (YS) is calculated as a fitting parameter by fittingexperimental T(RPM) dependence on increasing RPM sweep with thetheoretical one which was calculated assuming the so-called Cassonconstitutive equation and is implicitly given by the following equation:

${RPM} = {\frac{15}{\pi}{\int_{YS}^{SW}{\frac{\left( {S^{n} - {YS}^{n}} \right)^{1/n}}{{HSV}*S}{dS}}}}$

where HSV (high-shear viscosity limit) is another fitting parameter,n=0.3, and SW is the stress on the imaginary wall encompassing the vanewhich is estimated as follows:

${SW} = \frac{2T}{\pi \; {{LD}^{2}\left( {1 + \frac{D}{3L}} \right)}}$

T(RPM) is calculated from these two equations numerically. Only datapoints with RPM from 5 to 200 and T % between 3 and 100 are fitted.

TABLE 6 Static Yield Stress Days after Manufacturing Viscosity at 1 RPM(cP) (Pa) Comparative Example I 1 442984 152 21 277573 161 30 202798 13337 203931 99 90 167110 94 365 226817 40 Composition 11 1 609528 161 14527956 184 44 425990 187 75 431088 199 290 493401 250

The data described in Table 6 (above) demonstrates the unexpectedstabilizing effects provided by the inventive thickening systems of thepresent invention. Importantly, these effects are observed over anextended period of time, rather than being transient in nature.

Example 4

Table 7 (below) describes the formulas of two additional compositions ofthe present invention (Compositions 12 and 13) and another comparativeformula (Comparative Example II).

TABLE 7 Comparative Composition 12 Composition 13 Example II IngredientWt % GLYCERIN — 26.000000 35.000000 SORBITOL 39.000000 13.000000 —SUCRALOSE — — 0.020000 EP PURIFIED WATER 27.824737 28.244737 30.848737SODIUM SACCHARIN 0.400000 0.400000 0.400000 STANDARD ABRASIVE SILICA10.000000 10.000000 10.000000 SILICA-THICKENER 6.000000 6.0000007.000000 AMORPHOUS SILICA 5.000000 5.000000 5.000000 Na-LAURYL SULFATEGRANULES 2.105263 2.105263 2.105263 Flavor 1.500000 1.500000 1.500000L-ARGININE 1.500000 1.500000 1.500000 COCAMIDOPROPYL BETAINE 1.2500001.250000 1.250000 ZINC OXIDE 1.000000 1.000000 1.000000 TITANIUM DIOXIDE0.750000 — 0.300000 XANTHAN GUM 0.300000 0.300000 0.400000 SODIUM CMC -TYPE 12 — — 1.100000 HYDROXYETHYL CELLULOSE (HEC)* 0.800000 1.000000 —TETRASODIUM PYROPHOSPHATE 0.500000 0.500000 0.500000 ZINC CITRATETRIHYDRATE 0.500000 0.500000 0.500000 POLOXAMER 407 0.500000 0.5000000.500000 BENZYL ALCOHOL 0.400000 0.400000 0.400000 85% PHOSPHORIC ACID0.350000 0.350000 0.350000 SODIUM FLUORIDE - USP, EP 0.320000 0.3200000.320000 Additional Colorants — 0.130000 0.006000 *HEC having amolecular weight of about 350,000

Example 5

Table 8 (below) describes the percentage change in viscosity loss andloss of static yield stress for two exemplary compositions of thepresent invention (Compositions 12 and 13) and a comparative composition(Comparative Example II). Viscosity and Static Yield Stress werecalculated in accordance with the methods described in Example 3 herein.

TABLE 8 Viscosity Loss Loss of Static Yield Stress Composition (1 Year)(After 1 Year) Composition 12 19% Stable Composition 13 21% StableComparative Example II 49% 73%

The data described in Table 8 (above) not only shows that compositionsof the present invention demonstrate less viscosity loss and staticyield stress loss than a comparative composition, but it alsodemonstrates that the benefits are reproducible.

Example 6

Table 9 (below) describes an exemplary backbone for oral carecompositions of the present invention comprising—inter alia—a basicamino acid in free or salt form (e.g. L-arginine), and a combination ofzinc ion sources.

TABLE 9 L-Arginine 1.5 Glycerin 33.8 Zn Citrate Trihydrate 0.5 SodiumFluoride 0.32 Non-ionic surfactant 0.5 Alkali Phosphate salt 0.5 ZincOxide 1 Saccharin 0.4 Colorant 0.75 Silica Abrasive(s) 15 Silicathickener 7.5 Anionic surfactant 2 Flavoring agent 1.5 Preservative 0.4Amphoteric surfactant 1.25

Added to this backbone were the various combinations of water, anonionic cellulose ether (hydroxyethylcellulose [HEC]); and apolysaccharide gum (xanthan gum), described in Table 10 (below).

TABLE 10 Water Xanthan Gum HEC** Composition Wt. % 14 32.18 0.20 0.70 1532.18 0.70 0.20 16 32.18 0.70 0.20 17 32.18 0.52 0.38 18 32.05 0.70 0.3319 31.84 0.52 0.72 20 31.78 0.70 0.60 21 31.78 0.40 0.90 22 31.98 0.200.90 23 31.94 0.65 0.49 24 32.18 0.35 0.55 25 32.02 0.48 0.57 **HEChaving a molecular weight of about 300,000

Toothpastes were prepared from each of these combinations by firstcreating a gel comprising water, xanthan gum and hydroxyethylcellulose(HEC); and then combining each gel with the remaining components (seeTable 9) in a Ross double planetary mixer. The rheological profiles ofboth the gel pre-mixes and the toothpaste end products are evaluated.

Example 7

Gels are tested in ARES G2 rheometer by TA Instruments using Couettegeometry (standard DIN cell). Two tests are performed: shear rate sweepbetween 1 and 100 sec⁻¹ and frequency sweeps under small-amplitudeoscillations. The data of the shear rate sweeps are fitted with powerlaw, i.e.

Shear stress=K*shear rate^(n)

where consistency, K, and flow index, n, are listed in Table 11 (below).

Consistency can be as well thought of as viscosity at shear rate 1sec⁻¹. Flow index n=1 corresponds to Newtonian fluid, lower valuesindicate shear thinning with an extreme case of n=0 corresponding toyield stress fluid. From frequency sweeps only viscoelastic moduli at 1Hz are reported below in Table 11, elastic modulus G′ and viscousmodulus G″, as well as their ratio.

TABLE 11 Gel Parameters Composition K (Pa * s^(n)) n G′ (Pa) G″ (Pa)G′/G″ 14 3.53 0.5866 7.1 8.77 0.81 15 20.88 0.245 48.3 18.7 2.58 1623.16 0.243 45.7 17.5 2.61 17 13.72 0.3298 28.3 14.6 1.94 18 23.59 0.26949 20.5 2.39 19 17.48 0.4125 32.5 23.2 1.40 20 22.88 0.3409 48.6 26.91.81 21 12.29 0.4938 22.9 22.4 1.02 22 4.79 0.6171 8.3 12.15 0.68 2320.97 0.3278 43.3 22.4 1.93 24 7.11 0.4536 14.2 11.3 1.26 25 13.630.3918 26.7 17.4 1.53

Easy processability of the gel requires low viscosity, less shearthinning and less elasticity, which generally correlates with low valuesof K, G′ and G′/G″, but higher values of II. The exact limits on theseparameters depend on the actual design of the mixer.

Example 8

Static yield stress (YS) and viscosity at 0.25 s⁻¹ for the finishedtoothpaste end-products prepared based on the combinations described inTables 9 and 10, are evaluated. Measurements are performed on ARG2rheometer by TA Instrument using a cylindrical cup and vane uppergeometry. The measurements were performed in the same containers, inwhich the samples were aged. Those were standard 50 cc centrifuge tubes,available from VWR, into which the samples were placed at the time ofpreparation. Then the samples were consolidated by centrifuging at lowrotations in the centrifuge so as to remove air pockets and ageddirectly in these tubes at room temperature (RT) or at 49° C. for up to2 months. Before the measurements the heated tubes were allowed to coolfor 2 hours at room temperature and then inserted directly into the cupof the rheometer. To avoid the tubes mobility in the cup, they werewrapped with a thin layer of tape. The vane was inserted into the tubesand samples measured directly inside them. The measurement procedureclosely mimicked the one described above for Brookfield viscometer,i.e., a constant shear rate of 0.05 sec⁻¹ was applied for 400 sec andfollowed by shear rate sweeps up and down from 0.1 to 30 sec⁻¹. Hereshear rate is calculated from angular velocity of the vane, Q, followingTA Instruments conventions as follows:

$S = {\frac{1 + k^{2\;}}{1 - k^{2}}\Omega}$

where k is the ratio of the diameter of the vane to the diameter of thetube. Torque, T, on the shaft of the vane was measured. Yield stress wascalculated by fitting T(S) with the theoretical function calculatedassuming Casson constitutive equation and implicitly given by thefollowing equation:

$\Omega = {\frac{1}{2}{\int_{{SW}\; 0}^{SW}{\frac{\left( {S^{n} - {YS}^{n}} \right)^{1/n}}{{HSV}*S}{ds}}}}$

where HSV (high-shear viscosity limit) is another fitting parameter,n=0.2, and SW is the stress on the imaginary wall encompassing the vanewhich is estimated as follows:

${SW} = \frac{2T}{\pi \; {{LD}^{2}\left( {1 + \frac{D}{3L}} \right)}}$

and SW0 is the largest of the two values: YS and k²SW. Viscosity, V, atS=0.25 sec⁻¹ was calculated according to Casson equation as follows

$V = \left( {\left( \frac{YS}{S} \right)^{n} + {HSV}^{n}} \right)^{1/n}$

Note that the exponent n used to process these data is different fromthe one used to process Brookfield data above (0.2 instead of 0.3) toaccommodate a wide range of shear rates as measured by a rheometer.

The results of these evaluations are described in Table 12 (below).

TABLE 12 Paste Paste Paste aged at aged at RT aged at 49 C. RT for 1 wkfor 1 month for 2 month Viscosity Viscosity Viscosity YS at 0.25 s⁻¹ YSat 0.25 s⁻¹ YS at 0.25 s⁻¹ Composition (Pa) (cP) (Pa) (cP) (Pa) (cP) 141.7 50,232 17.4 85,022 2.2 55,034 15 25.2 173,848 48.3 222,280 29.0183,000 16 24.8 167,895 42.6 204,157 26.8 176,172 17 11.9 102,691 42.6204,157 13.4 106,199 18 26.0 180,787 52.1 214,586 27.6 188,500 19 12.1161,077 26.0 168,495 13.4 161,060 20 23.4 210,000 50.5 241,336 30.7236,770 21 7.7 138,867 26.0 164,016 10.8 146,088 22 4.6 87,257 14.9106,338 8.4 110,207 23 31.2 231,467 53.7 250,236 44.7 249,000 24 5.881,449 24.2 111,160 N/a N/a 25 9.0 120,471 34.1 155,823 13.0 133,262

The data described in Table 12 (above) demonstrates that exemplarycompositions of the present invention will maintain their shape on thebrush, while also being easily squeezed from a toothpaste tube.

As used throughout, ranges are used as shorthand for describing each andevery value that is within the range. Any value within the range can beselected as the terminus of the range. In addition, all references citedherein are hereby incorporated by referenced in their entireties. In theevent of a conflict in a definition in the present disclosure and thatof a cited reference, the present disclosure controls.

Unless otherwise specified, all percentages and amounts expressed hereinand elsewhere in the specification should be understood to refer topercentages by weight. The amounts given are based on the active weightof the material.

While the present invention has been described with reference toembodiments, it will be understood by those skilled in the art thatvarious modifications and variations may be made therein withoutdeparting from the scope of the present invention as defined by theappended claims.

What is claimed is:
 1. An oral care composition comprising: a. a basicamino acid in free or salt form wherein the basic amino acid is selectedfrom arginine, lysine, and a combination thereof; b. a combination ofzinc ion sources; and c. a thickening system comprising: i. from about0.1 wt. % to about 1 wt. % of a nonionic cellulose ether; and ii. fromabout 0.25 wt. % to about 1 wt. % of a polysaccharide gum.
 2. The oralcare composition according to claim 1, wherein the nonionic celluloseether has a viscosity, measured at 2% in water at 25° C., of from about150 to about 400 cps.
 3. The oral care composition according to claim 1,wherein the nonionic cellulose ether has a molecular weight of fromabout 300,000 to about 350,000.
 4. The oral care composition accordingto claim 1, comprising from about 0.25 wt. % to about 1 wt. % of thenonionic cellulose ether.
 5. The oral care composition according toclaim 1, comprising from about 0.5 wt. % to about 1 wt. % of thenonionic cellulose ether.
 6. The oral care composition according to anyclaim 1, comprising from about 0.6 wt. % to about 0.9 wt. % of thenonionic cellulose ether.
 7. The oral care composition according toclaim 1, comprising 0.5 wt. %, 0.6 wt. %, 0.7 wt. %, 0.8 wt. %, 0.9 wt.% or 1 wt. % of the nonionic cellulose ether.
 8. The oral carecomposition according to claim 1, wherein the nonionic cellulose ethercomprises hydroxyethylcellulose.
 9. The oral care composition accordingto claim 1, comprising from about 0.3 wt. % to about 0.9 wt. % of thepolysaccharide gum.
 10. The oral care composition according to claim 1,comprising from about 0.4 wt. % to about 0.9 wt. % of the polysaccharidegum.
 11. The oral care composition according to claim 1, comprising fromabout 0.5 wt. % to about 0.9 wt. % of the polysaccharide gum.
 12. Theoral care composition according to claim 1, comprising from about 0.6wt. % to about 0.9 wt. % of a polysaccharide gum.
 13. The oral carecomposition according to claim 1, comprising about 0.3 wt. %, about 0.4wt. %, about 0.5 wt. %, about 0.6 wt. %, about 0.7 wt. %, about 0.8 wt.% or about 0.9 wt. % of a polysaccharide gum.
 14. The oral carecomposition according to claim 1, wherein the polysaccharide gum isxanthan gum.
 15. The oral care composition according to claim 1, whereinthe thickening system further comprises from about 5 wt. % to about 10wt. % silica.
 16. The oral care composition according to claim 1,wherein the thickening system comprises from about 0.5 wt. % to about 15wt. % of the oral care composition.
 17. The oral care compositionaccording to claim 1, wherein the nonionic cellulose ether and thepolysaccharide gum are present in a weight ratio of from about 3:1 toabout 1:2.
 18. The oral care composition according to claim 1, whereinthe nonionic cellulose ether and the polysaccharide gum are present in aweight ratio of from about 2:1 to about 1:1.
 19. The oral carecomposition according to claim 1, wherein the nonionic cellulose etherand the polysaccharide gum are present in a weight ratio of about 1:1.20. The oral care composition according to claim 1, wherein the nonioniccellulose ether and the polysaccharide gum are present in a weight ratioof 3:1, 2.5:1, 2:1, 1.5:1 or 1:1.
 21. The oral care compositionaccording to claim 1, wherein the combination of zinc ion sourcescomprises zinc oxide and zinc citrate.
 22. The oral care compositionaccording to claim 1, wherein the amino acid is arginine, and is presentat about 1.5 wt. %, 5 wt. %, or about 8 wt. %, of the oral carecomposition.
 23. The oral care composition according to claim 21,wherein the weight ratio of zinc oxide to zinc citrate is about 2:1. 24.The oral care composition according to claim 21, wherein the zinccitrate is in an amount of about 0.5 wt. % and zinc oxide is present inan amount of about 1.0 wt. % based on the total weight of the oral carecomposition.
 25. The oral care composition according to claim 1, furthercomprising a fluoride ion source selected from sodium fluoride, sodiummonofluorophosphate, and stannous fluoride.
 26. The oral carecomposition according to claim 25, wherein the fluoride ion sourceprovides soluble fluoride in an amount of about 1450 ppm.
 27. The oralcare composition according to claim 25, wherein the fluoride ion sourcecomprises stannous fluoride.
 28. The oral care composition according toclaim 1, comprising: a. about 1.0 wt. % zinc oxide; b. about 0.5 wt. %zinc citrate; c. about 1.5 wt. % L-arginine; d. from about 0.5 wt. % toabout 1 wt. % of hydroxyethylcellulose; and e. from about 0.3 wt. % toabout 0.8 wt. % of xanthan gum.
 29. The oral care composition accordingto claim 28, comprising from about 0.3 wt. % to about 0.6 wt. % ofxanthan gum.
 30. The oral care composition according to claim 28,comprising from about 0.7 wt. % to about 0.8 wt. % of xanthan gum. 31.The oral care composition according to claim 1, wherein the oral carecomposition is in a form selected from: a toothpaste, a mouthwash, and agel.
 32. The oral care composition according to claim 1, having a staticyield stress greater than about 20 Pa, about 25 Pa, about 30 Pa, about35 Pa, or about 40 Pa.
 33. The oral care composition according to claim1, having a drainage time of less than 10 minutes.
 34. The oral carecomposition according to claim 1, demonstrating less than 225 grams ofleft-overs.
 35. The oral care composition according to claim 1, whereinthe oral care composition loses no more than about 25% of its initialviscosity after one year.
 36. A method to improve oral health comprisingapplying an effective amount of the oral care composition according toany foregoing claim to the oral cavity of a subject in need thereof,wherein the method is effective to: i. reduce or inhibit formation ofdental caries, ii. reduce, repair or inhibit early enamel lesions, e.g.,as detected by quantitative light-induced fluorescence (QLF) orelectrical caries measurement (ECM), iii. reduce or inhibitdemineralization and promote remineralization of the teeth, iv. reducehypersensitivity of the teeth, v. reduce or inhibit gingivitis, vi.promote healing of sores or cuts in the mouth, vii. reduce levels ofacid producing bacteria, viii. to increase relative levels ofarginolytic bacteria, ix. inhibit microbial bio film formation in theoral cavity, x. raise and/or maintain plaque pH at levels of at least pH5.5 following sugar challenge, xi. reduce plaque accumulation, xii.treat dry mouth, xiii. enhance systemic health, including cardiovascularhealth, xiv. whiten teeth, xv. reduce erosion of the teeth, xvi.immunize (or protect) the teeth against cariogenic bacteria and theireffects, and/or xvii. clean the teeth and oral cavity.